package demo_JUC.PandC;

import java.util.Date;

/**
 * 线程之间的通信问题：生产者和消费者问题！
 * -- 等待唤醒，通知唤醒
 * 线程交替执行 A B 操作同一变量
 * A num+1
 * B num-1
 */
public class demo {
    public static void main(String[] args) throws InterruptedException {
        Data data = new Data();

        new Thread(()->{for (int i = 1; i < 50 ; i++){
            try {
                data.increment();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }}, "A").start();
        new Thread(()->{for (int i = 1; i < 50 ; i++){
            try {
                data.decrement();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }}, "B").start();
        new Thread(()->{for (int i = 1; i < 50 ; i++){
            try {
                data.increment();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }}, "C").start();
        new Thread(()->{for (int i = 1; i < 50 ; i++){
            try {
                data.decrement();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }}, "D").start();
    }
}

// 等待，处理，通知
class Data{
    private int number = 0;
    public synchronized void increment() throws InterruptedException {
        while (number != 0){
            // 等待
            this.wait();
        }
        number++;
        System.out.println(Thread.currentThread().getName() + "=>" + number);
        this.notifyAll();
    }
    public synchronized void decrement() throws InterruptedException {
        while (number == 0){
            // 等待
            this.wait();
        }
        number--;
        System.out.println(Thread.currentThread().getName() + "=>" + number);
        this.notifyAll();
    }
}